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Updated: Feb 13, 2026

Four-Dimensional CT Analysis Using Sequential 3D-3D Registration
Published on: November 23, 2019
Interlaboratory comparison of femur surface reconstruction from CT data compared to reference optical 3D scan
Ehsan Soodmand1, Daniel Kluess2, Patrick A Varady3
1Biomechanics and Implant Technology Research Laboratory, Department of Orthopaedics, University Medicine Rostock, Doberaner Strasse 142, 18057, Rostock, Germany. ehsan.soodmand@gmail.com.
Background:
The present study contrasts the accuracy of different reconstructed models with distinctive segmentation methods performed by various experts. Seven research groups reconstructed nine 3D models of one human femur based on an acquired CT image using their own computational methods. As a reference model for accuracy assessment, a 3D surface scan of the human femur was created using an optical measuring system. Prior to comparison, the femur was divided into four areas; "neck and greater trochanter", "proximal metaphysis", "diaphysis", and "distal metaphysis". The deviation analysis was carried out in GEOMAGIC studio v.2013 software.
Results:
The results revealed that the highest deviation errors occurred in "neck and greater trochanter" area and "proximal metaphysis" area with RMSE of 0.84 and 0.83 mm respectively.
Conclusion:
In conclusion, this study shows that the average deviation of reconstructed models prepared by experts with various methods, skills and software from the surface 3D scan is lower than 0.79 mm, which is not a significant discrepancy.
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